Saponaria. Saponaria officinalis L. Soapwort. Bouncing Bet. Fuller's Herb. Sheep Weed. Saponaire. Savonniere, Fr. Seifenwurzel, G. (Fam. Caryophyllaceae.)—A perennial, herbaceous plant, having large rose-colored flowers, which are commonly double. It is common along roadsides and waste places in the United States. The rhizome and roots are employed. The rhizomes are cylindrical, from 5 to 12 cm. long and 5 to 12 mm. thick, outer surface being reddish-brown. The fracture is short and even. They are inodorous, and of a taste at first bitterish and slightly sweetish, afterwards somewhat pungent, continuing long, and leaving a slight sense of numbness on the tongue. They impart to water the property of forming a lather when agitated, like a solution of soap, whence the name of the plant was derived. This property, as well as the medicinal virtues of the plant, resides in saponin, C32H54O18. This principle constitutes, according to Bucholz, its discoverer, 34 per cent. of the dried root which contains also a considerable quantity of gum and a little bassorin, resin, and altered extractive, besides lignin and water. For description of saponin, see Quillaja. Saponin has been found in many other plants, among them some species of Silene, Dianthus, and Lychnis, in Vaccaria vulgaris Host., and in Agrostemma Githago L., all belonging to the fam. Caryophyllaceae. (J. P. C., 3e ser., x, 339; also P. J., 1871, 585; Australian Journ. Pharm., 1887.) Serious poisonings by the mixture of the seeds of Agrostemma Githago with wheat have been reported. (D. M. W., 1903.) According to Augustine Henry, there are at least eleven species of trees whose products are used in China for washing purposes and probably contain saponin, which is also found to the extent of 10 per cent. in the seeds of the Chinese tea oil tree, and is left in such large proportion in the refuse after the extraction of the oil that the "tea seed cake" is used as a fish poison. (Am. Drug., 1896.) In California the Indian Soap Root, Chlorogallum pomeridianum (Ker.) Kunth., is much used for washing clothes; it probably contains saponin. The fruits of various species of Sapindus are also rich in saponin and are used as detergents accordingly.
The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.